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Penalty doubles.

#1 User is offline   Orla 

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Posted 2003-June-04, 11:59

I am a wimp when it comes to penalty doubles >:(. But I know, doubling, or not doubling, is sometimes a matter of a top or a bottom. Lately I have been hearing: "you should have doubled", way too often. :-[

How can you be sure Opps really can't make that contract and it is just a sacrifice? :P

I have noticed, too, that very often doubling in IMPs make little difference to the score ;D - not so in MPs ;)

Any chance of some basic guidelines as to when it is a good time to penalize Opps. My biggest problem is when my hand is weakish and I should be doubling on what P has said to me. ::) ::)

Thanks, Orla ::)
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#2 User is offline   lenze 

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Posted 2003-June-04, 12:48

You are correct in observing that doubles are different at IMPs as opposed to MPs. At IMPs, one tends to double less. So let's look at MPs. On competitive hands , one needs to determine "whose hand is it?" If you judge the opponents have the balance of power, say 22-24 HCPs, it is their hand. Your goal is the smallest minus. If you judge the points are divided evenly (you hold 19,20,or21), your goal is ANY PLUS. It's when your side, however, holds the 22-24 points you must be aggresive in doubling. Your goal is now the GREATEST PLUS. WARNING: No guarentees. If they do not make 1 out o 5 doubled contracts against you at MPs, you are NOT doubling enough.
(actually, I believe 1 out of 4 is acceptable if the other parts of your game are up to par)

Just my thought, I could be wrong
Please do not complain about my opinion. I don't have the time to convince you I'm right.
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#3 User is offline   inquiry 

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Posted 2003-June-04, 14:11

Hi Orla,

Doubling and type of game is an interesting topic. The premise that you double less at IMPs is correct for part-scores. This is because going from +50 to +100 or +100 to +200 is just too few imps to risk going from -110 to -470 or 670. You have to be pretty sure of setting it at imps before you double. At matchpoints, there is no need to worry too much about how much it will cost you if you double and are wrong. If you think there is a pretty good chance they will not make it, you should double (or of course bid on if you think you can score more by doing so).

It is this frequency of gain at matchpoints that make low level double more attractive. It's funny, but high level doubles often swing the other way around, with more doubles at imps. Say you bid 4H at equal vul and the opponents bid 4S as a sacrafice. You are certain 4S is down two, and equally feel sure you would make 4H. At imps, you most often double. Sure you might make more at 5H, but 5H down one is a total disaster, converting +300 or +500 (down two X) into minus -50 or -100. At matchpoints, however, it is frequency of gain again. If you think more of the time you will make 5H then you should bid on.

Let's look at a small table. Assume you have 60% chance of making 5H and both sides vul. Likewise assume you are down one not doubled when it fails to make.

5H +650 win 4 imps to 4SX +500
5H -100 lose 12 imps to 4H +620 (or to 4Sx +500)*

(*12 imps is +600 to +740... your minus 600 or 720 if you bid 5H and are wrong, so it is 12 imps either way)

In this model, bidding 5H cost you an average of 2.4 imps/board. The reason. The 60% time it makes 5H you do 4 imps better than double. The 40% of the time you go down, you do 12 imps worse than double... 0.6*4 + 0.4*(-12) = -2.4 for bidding on.

Now if your odds of making are better, say 70%? Double is still mathematically the winner. Of course, you might beat it only 1 or 3, and they might double you. But you see why high level doubles are more likely at imps than mp. At MP, if you thought you had 60% chance of better score by bidding, you should bid, and if you think its 70% you bid it in a flash.

Now, for doubling in general. In matchpoints in competitive auctions, you should be doubled, or double them, a fairly reasonable percentage of time. I am not sure what this percentage is, but if you think you can beat them, you should probably double, and if you think you can't beat them, on many of the hands you should take another bid (don't go for -200 if you can help it) and they might then double you. Lenze suggested they should make 1 in 5 or 1 in 4 of your doubles or you are not doubling enough. Heck, at MP, maybe they should make 1 in 3 or you are not doubling often enough. I know I double a lot of part-score contracts at MP that make, but in the long run, doubling fairly often seems to be a winning strategy for me.

Now, of course it is not this simple, but you get the idea... it is the frequency of gain for the double, that is the deciding factor at MP. At imps, it the size of the potential gain/loss that counts.

Ben
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#4 User is offline   lenze 

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Posted 2003-June-04, 14:33

Quote


Lenze suggested they should make 1 in 5 or 1 in 4 of your doubles or you are not doubling enough. Heck, at MP, maybe they should make 1 in 3 or you are not doubling often enough. I know I double a lot of part-score contracts at MP that make, but in the long run, doubling fairly often seems to be a winning strategy for me.


Ben



I agree, Ben. I can live with 1 out of 3. It's my fragile partners that go south on me.

lenze
Please do not complain about my opinion. I don't have the time to convince you I'm right.
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#5 User is offline   inquiry 

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Posted 2003-June-04, 14:43

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I agree, Ben. I can live with 1 out of 3. It's my fragile partners that go south on me.


;) :P Yup, online I lose more partners after low level matchpoint doubles than anything else.... and some of those are even after we set the contract. Usually with a comment like,

WHAT ARE YOU DOUBLING ON ? ? ? ??
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#6 User is offline   Rado 

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Posted 2003-June-05, 03:38

Hi Orla,
One more helpful topic especially when part-score battle at MP's: when feeling opps may go down always look at your fit for partner's suit already bidded - when you are short 0-1 cards green light, when you have 2 cards in P's suit - yellow light (must have more outside for double), and when 3+fit then think about bidding or pass to hear P's decision. The Law of Total Tricks (LOTT) is very useful when borderline decisions needed.

In continuation of Lenze's and Ben's words we have old bulgarian saying:
"At MP's if Opps make 3 of 5 doubled then you're doubling too much, if they make 2 of 5 then you're doubling not enough" LOL

Best regards, Rado
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#7 User is offline   Cave_Draco 

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Posted 2003-June-05, 13:24

A view that is applicable to most of us?

Playing MP; opps go down: who doubled?

Can you blame P? Or is it a team effort, ;D.
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